Non-refillable valve

ABSTRACT

A nonrefillable valve is provided that allows for an initial filling of a container, but prevents subsequent refilling of the container. The valve operating assembly includes a valve stem and a valve core which is slidably received in the distal end of the valve stem. In a first position, the valve core resides above a rim or protrusion within the chamber. After filling of the container, a second position is defined when the valve stem is operated to force the valve core beyond the protrusion and in seating engagement with a valve seat, thus sealing the container. The valve is then selectively operated in a third or open position to discharge the container as desired. Subsequent refilling of the container is prevented by the force of fluid reentering the valve which forces the valve core to its seated engagement with the valve seat.

REFERENCE TO RELATED APPLICATIONS

This is a continuation application of U.S. patent application Ser. No.09/948,328 filed on Sep. 6, 2001, now U.S. Pat. No. 6,595,486 andentitled “Non-refillable Valve”, which is incorporated herein byreference in its entirety.

FIELD OF THE INVENTION

This invention relates to nonrefillable or single use valves used inpressurized systems. More particularly, the invention relates to anonrefillable valve especially adapted for use with pressurized vesselsor containers wherein the construction of the valve allows the pressurecontainer to be filled once, and then selectively discharged; however,subsequent refill of the pressure container is prevented.

BACKGROUND OF THE INVENTION

Valves are commonly used to control the discharge of fluid from apressure container or vessel. Typically, such valves include a handle orsome other means by which a user can selectively control discharge ofthe container. Pressure containers may contain any number of productssuch as butane, propane, refrigerant gas, or any number of other typesof industrial gases.

Due to governmental regulations in the United States, pressurecontainers containing refrigerants may only be filled once. Thus, suchpressure containers can be initially charged or filled with therefrigerant; however, once the refrigerant has been discharged from thecontainer, the container may not be refilled again.

There are a number of prior art valves which exist not only for use withnon-refillable containers, but also refillable containers. One group ofpatents representative of valves which are used in conjunction withnonrefillable containers include patents assigned to Amtrol, Inc., ofWest Warwick, Rhode Island. One specific example includes the U.S. Pat.No. 4,813,375. This reference discloses a nonrefillable valve includinga housing with a central bore, and three distinct portions within thecentral bore of particular diameters. The lower portion of the centralbore is narrower than a middle portion which in turn is narrower than anupper portion. The lower end of the valve housing sealingly engages thepressure container. A valve stem is rotatably positioned in the upperportion of the central bore. The valve stem itself includes a verticalbore formed in its bottom portion. A resilient valve sealing member isslidably received in the bore of the valve stem. When the pressurecontainer is filled, a top rim portion of the sealing member ispressingly positioned in the upper portion of the central bore. Afterfilling, the valve sealing member is pushed downward into the middleportion which allows the valve to contact a seating surface thus sealingthe pressure container. A non-compressed top rim of the sealing memberis wider than the upper portion of the central bore, which prevents thesealing member from moving back up into the upper portion of the centralbore. If an attempt is made to refill the container, the sealing memberengages the seating surface thus preventing refill. Additional U.S.patents disclosing similar valves include the U.S. Pat. Nos. 5,295,502;4,573,611; and 5,036,876.

While the foregoing references may be adequate for their intendedpurposes, there is still a need for a valve of simple and reliableconstruction which prevents refilling of a pressure container.

SUMMARY OF THE INVENTION

One object of the present invention is to provide a nonrefillable valvefor pressure containers, for example, cylinders used in industrialapplications to hold and store pressurized industrial gas. Anotherobject of the invention is to provide a valve which easily permitsdischarge of the pressure container, but will automatically preventrefilling of the container without the user or operator of the valvehaving to further manipulate the valve. Another object of the inventionis to provide the above described functionality with a valve of simpleand reliable construction.

The structure of the valve of the present invention includes a valvebody having a longitudinal chamber extending therethrough. A lowerportion of the chamber communicates with the opening or orifice of apressure container to which the valve is attached. A valve stem ispositioned within the chamber. A handle is integral with an upperportion of the valve stem providing a means for a user to manipulate thepositioning of the valve stem within the chamber. A valve core isslidably received in a bore formed on the lower end of the valve stem.The valve core includes a sealing member formed on the lower portionthereof. A nozzle attaches to the valve body, the nozzle including anorifice or passageway which communicates with the chamber of the valvebody. A transverse opening formed on the sidewall of the valve bodycommunicates between the nozzle passageway and the chamber.

An inner concentric rim, flange, or protrusion is formed on the internalsidewall of the chamber adjacent the passageway of the nozzle. When theempty pressure container is to be filled with a pressurized fluid, thevalve core is placed in a first open position wherein a larger diameterportion of the valve core flange resides in the chamber above the innerconcentric rim. In this first position, fluid may flow through thenozzle passageway into a lower portion of the chamber, and then throughan opening or orifice communicating with the pressure container. Afterthe pressure container has been filled, the handle is operated to movethe valve stem downwardly within the valve body thus forcing the valvecore flange beyond the inner concentric rim. The valve stem can be movedto force the sealing member of the valve core against a valve seat whichseals the pressure container, thus defining a second closed position.

In order to evacuate or empty the contents of the pressure container,the handle is unscrewed thereby raising the valve stem, and allowing thesealing member to be unseated from engagement with the valve seat. Fluidpressure raises the valve core allowing the fluid to escape the pressurecontainer back through the lower portion of the chamber and back throughthe nozzle passageway.

Refilling of the pressure container is prevented even when the valvestem is raised to allow the sealing member to be unseated. This isaccomplished due to contact between the upper surface of the valve coreflange and the inner concentric rim, thereby preventing the valve coreflange from being positioned above the inner concentric rim. A thirdposition is therefore defined when the valve stem is raised to allow thevalve core to be unseated from the valve seat. In this third position,the majority of the area of the nozzle passageway communicating with thechamber resides above the valve core flange. In other words, atransverse opening into the chamber is created where the nozzleintersects the internal sidewall of the chamber, and the majority thecross-sectional area of this opening lies above the inner concentricrim, and likewise, above the valve core flange. Therefore, a pressurizedflow of fluid entering the nozzle passageway results in a greatermajority of such flow entering the portion of the chamber above thevalve core flange, thus forcing the flange downwardly, and therebyresulting in the sealing member engaging the valve seat. Because thevalve core is freely slidable within the bore of the valve stem, thereis no means by which to operate the handle in order to place the valvecore back in its first position. In this manner, the valve of thepresent invention functions as a check valve to prevent refill of thecontainer

In addition to an inner concentric rim, other constricting structurescan be provided to prevent the valve core from returning to its firstposition once a user closes the valve. For example, one or more arc likesegments, or one or more protrusions may extend from the inner wall ofthe valve body into the chamber, thereby constituting the constrictionwhich must be overcome by the particular sized valve core flange.

The valve core may be one integral unit made of a resilient material,such as natural or synthetic rubber. Alternatively, the valve core mayinclude a valve core body, and a sealing member which includes aresilient sealing surface for engagement with the valve seat. The valvecore flange can also be shaped to accommodate the particularconstriction formed within the chamber. The valve core flange can beshaped or configured allowing it to be compressed or moved downwardlypast the constriction without undue force, yet the valve core flangeconfiguration makes it much more difficult to return the valve core toits first position. For example, the lower end of the valve core flangecan be slightly tapered, while the upper end can have a distinct edge orcorner preventing it from being easily forced upwardly beyond theconstriction.

Other features and advantages of the invention will become apparent froma review of the drawings, taken in conjunction with the followingwritten description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a pressure vessel or container receivinga flow of fluid from a product source, and illustrating thenonrefillable valve of the invention installed on the pressurecontainer;

FIG. 2 is an exploded perspective view of the nonrefillable valve ofthis invention illustrating the component parts thereof including afragmentary perspective view of the valve body;

FIG. 3 is a vertical section illustrating the internal components of thevalve, and operation of the valve when the pressure container is beingfilled or charged;

FIG. 4 is another vertical section illustrating the valve moved to itsclosed position;

FIG. 5 illustrates another vertical section when the valve is openedthus allowing fluid flow out of the pressure container; and

FIG. 6 is another vertical section illustrating the valve in the openposition; however, preventing the pressure container from beingrefilled.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 1, a pressure container or pressure vessel C isprovided with the nonrefillable valve 10 of the invention for fillingand selective emptying of the container C. Valve 10 can be welded,threaded or otherwise affixed to the container C. In order to fill thecontainer, a product source P produces a flow of fluid through line Lwhich communicates with the valve 10. Container C simply represents acommon industrial cylinder or tank which is specifically designed tohold a pressurized fluid/gas therein.

Now referring to FIGS. 2 and 3, the primary components of the valve 10include a valve body 12 and a valve operating assembly 13, including anumber of working parts which are received in the valve body whenassembled. The valve body 12 is a cylindrical shaped member including achamber extending longitudinally therethrough. When the valve operatingassembly 13 is positioned within the chamber, the chamber can beconceptually separated into an upper portion 14, a middle portion 16,and a lower portion 18. As well understood by those skilled in the art,the valve body may be made of a suitable metal such as aluminum orstainless steel. The inner or interior surface 17 defining the chamberof the valve body includes a restriction or constriction 19, shown inthe form of a machined inner concentric rim 19 formed on the innersurface 17. In lieu of a continuous concentric rim, this feature couldinclude one or more segmented protrusions formed on the inner surface 17which extend into the chamber and provide a narrowed or constricted areawithin the chamber. An orifice or passageway 20 communicates with thelower portion 18 of the chamber, and this passageway 20 communicatesdirectly with the interior opening 21 of the pressure container. A valveseat 22 is provided at the interface or junction between lower portion18 of the chamber and passageway 20. As shown in FIG. 3, the pressurecontainer C includes an internally threaded neck 23 which receives thethreaded extension 24 of the valve body.

The handle 30 is provided for manipulating the valve operating assembly.The handle 30 connects or is integral with a valve stem which extendsinto the chamber. An upper portion 32 of the valve stem resides in theupper portion 14 of the chamber. As shown, upper portion 32 has anexternally threaded area 33 which is threaded into the upper portion 14of the chamber which may include a set of matching internal threads.Alternatively, as shown in the Figures, the upper portion 14 of thechamber can have a cylindrical insert 26 which is press fit into theupper portion 14 of the chamber. Accordingly, the cylindrical insert 26would be threaded on its interior surface to accommodate the externalthreads 33 of the valve stem. The lower portion 34 of the valve stemfurther extends into the middle portion 16 of the chamber. The lowerportion 34 includes one or more grooves 35 which have O-rings 38 mountedthereover. The distal or lower end of the valve stem has a cylindricalbore 36 formed therein. As shown in FIG. 3, the bore 36 extendssubstantially the length of the lower portion 34 of the valve stem.

A valve core 40 is slidably received within the valve stem bore 36.Valve core 40 includes an upper cylindrical section which is receivedwithin the bore 36, and includes a valve core flange 42 having a largercross sectional area or diameter in comparison to the upper cylindricalsection of the valve core. The valve core 40 is further defined by asubstantially flat upper edge 44 of the valve core flange 42. A sealingmember 46 is attached to the distal end of the valve core 40. Sealingmember 46 may be attached as by screw 48, or may be simply glued to thedistal end of the valve core. A nozzle 52 extends transversely withrespect to the longitudinal axis of the valve body 12. Nozzle 52 maysimply be a cylindrical shaped extension including a passageway 50 whichcommunicates directly with the chamber of the valve body. Passageway 50is located to intersect with inner concentric rim 19. Therefore, innerconcentric rim 19 terminates at the passageway 50. As also shown, agreater cross sectional area defining the passageway 50 extends aboverim 19 as opposed to the cross sectional area of passageway 50 extendingbelow rim 19.

After the valve operating assembly 13 is inserted within the chamber ofthe valve body, the upper end 56 of the valve body may be crimped toretain the valve operating assembly 13 therein. In order to preventinadvertent actuation of handle 30, the safety clip 58 may be engaged inslot 59 to prevent the handle from being rotated. Additionally, a cap 54may be provided to cover the nozzle 52 prior to use.

Now the operation of the valve will be explained with respect to FIGS.3-6. FIG. 3 illustrates the valve 10 when the cylinder C is beingfilled. As shown, line L introduces a flow of fluid through passageway50, through lower portion 18 of the chamber, through orifice 20 and intothe interior opening 21 of the container C. The valve core 40 ispositioned such that the valve core flange 42 resides above the innerconcentric rim 19. After the container C has been filled, the retainingclip 58 is removed, and the handle 30 is operated to close the valve.Specifically, the handle is rotated causing the valve stem to displacedownwardly into the chamber. As the valve stem moves, it forces thevalve core flange 42 beyond the inner concentric rim 19. The valve coreflange is of sufficient resiliency that it can be forced beyond the rim19 without permanent deformation. When the handle is fully screwed down,the sealing member 46 closes off the orifice 20 by firmly contacting thevalve seat 22. The position of the valve in FIG. 3 can be defined as thefirst or pre-position, and the position of the valve in FIG. 4 can bedefined as the second or closed position.

When it is desired to evacuate the fluid within the container, thehandle 30 is unscrewed thus raising the valve stem within the chamber.The valve stem is raised to an extent which allows the sealing member 46to separate from contact with valve seat 22. Accordingly, fluid may thenflow out of the pressure container through orifice 20, lower portion 18of the chamber, and finally back through passageway 50 of the nozzle.Because the upper portion of the valve core is freely slidable withinthe valve stem bore 36, the valve core 40 rises in response to thepressurized fluid within the container C. However, the constrictioncreated by the inner concentric rim 19 prevents the valve core flange 42from displacing above the rim 19. The valve core flange 42 is sized withrespect to the inner concentric rim 19 such that pressurized fluidwithin the container cannot provide enough force to push or force thevalve core flange 42 back above the inner concentric rim 19. Theposition of the valve shown in FIG. 5 can be defined as a thirdposition, or an open position. As shown in FIG. 6, when the valve is inthe open position, refilling of the container is prevented. If flow offluid is reintroduced through passageway 50, the majority of flowthrough passage 50 enters the chamber above the valve core flange 42.Centerline X—X of passageway 50 illustrates that the majority of theinner concentric rim 19 lies below the centerline X—X of the passageway50. O-rings 38 prevent flow of fluid upwardly through the valve chamber.Accordingly, the middle portion 16 of the chamber becomes pressurizedthus forcing the valve core 40 downwardly in sealing engagement withvalve seat 22.

FIG. 5 illustrates that some fluid may escape the chamber into thepassageway 50 on all sides of the valve core flange 42. This is becausethere is no need to effectively seal the upper edge 44 of the valve coreflange 42 with respect to the inner concentric rim 19. So long as thereis some gap between the inner surface 17 and the inner surface 53defining the passageway 50, a controlled amount of fluid will be able toescape from the cylinder in the open position.

Although the invention has been primarily described for use with acompressed gas container, the invention can also be used with otherpressurized fluid containers or other pressurized liquid systems.

The simple design of the valve operating assembly allows the valve to bepositioned in either an open or closed position, and also automaticallyprevents refill of the container by the independent movement of thevalve core with respect to the valve stem. This simple slidingrelationship between the valve stem and valve core allows the valve tofunction as a check valve to prevent refilling of the container.

The valve stem may be machined of durable, lightweight metal such asaluminum. The valve core may be constructed of a suitably strengthenedplastic or rubber. The sealing member itself is preferably made of aresilient rubber material.

Although the invention has been described with respect to a preferredembodiment, it shall be understood that the invention is not so limitedbecause other variations and modifications are intended to be coveredwithin the spirit and scope of the invention.

What is claimed is:
 1. A non-refillable valve adapted for use with apressure container, said valve comprising: a valve body having an innersurface defining a longitudinally extending chamber extendingtherethrough, said chamber having a lower portion communicating with thepressure container to allow selective filling and discharge of saidcontainer, said chamber including a valve seat positioned in said lowerportion of said chamber, said inner surface having a concentricallyoriented protrusion extending from said inner surface into said chamber,and a transverse opening formed in said valve body and communicatingwith said valve chamber, said protrusion intersecting said transverseopening; a valve stem disposed in said chamber and being movable in saidchamber, said valve stem including a valve core communicating with saidvalve stem, said valve core being independently movable in said chamberrelative to said valve stem, said valve core including a flange; and atleast one O-ring abutting said inner surface of said valve body forsealing said valve stem with respect to said valve body; wherein saidvalve operates to allow fluid to flow through said opening and chamberto fill the container when said valve stem is in a first position, andwherein the valve core is in an uncompressed state within said chamberwhen said valve stem is in said first position.
 2. A non-refillablevalve, as claimed in claim 1, wherein said valve operates to seal thecontainer to prevent filling and discharge of the container when saidvalve stem is placed in a second position, the second position achievedby extending an end of said valve stem below said protrusion and forcingsaid valve core beyond said protrusion and into contact with said valveseat.
 3. A non-refillable valve, as claimed in claim 1, wherein: saidvalve stem has a bore formed therein, and said valve core is slidablyreceived in said bore and movable in said bore as influenced by thepositioning of said valve stem and by pressure of a fluid entering orexiting said valve.
 4. A non-refillable valve, as claimed in claim 1,wherein: said valve further includes a handle integral with said valvestem for operating said valve stem.
 5. A non-refillable valve, asclaimed in claim 1, wherein: said valve stem is positionable in a thirdposition to allow flow of fluid out of said pressure container and backthrough said chamber and said transverse opening; however, said thirdposition preventing flow of fluid through said transverse opening andsaid chamber into the pressure container, thus preventing the refillingof the container.
 6. A non-refillable valve, as claimed in claim 5,wherein: said third position is defined by said valve stem being raisedto a level allowing said valve core to slide upward in response to fluidpressure from the container, or slide downward in response to pressurefrom fluid entering the chamber, said downward movement of said valvecore causing said valve core to seal itself with respect to said valveseat.
 7. A non-refillable valve adapted for use with a pressurecontainer, said valve comprising: a valve body having an inner surfacedefining a longitudinally extending chamber extending therethrough, saidchamber having a lower portion communicating with the pressure containerto allow selective filling and discharge of said container, said chamberincluding a valve seat positioned in said lower portion of said chamber,said inner surface having a concentrically oriented protrusion extendingfrom said inner surface into said chamber, and a transverse openingformed in said valve body and communicating with said valve chamber,said transverse opening intersecting said protrusion; a valve stemdisposed in said chamber and being movable in said chamber, said valvestem including a valve core communicating with said valve stem, saidvalve core being independently movable in said chamber relative to saidvalve stem; and wherein said valve operates to allow fluid to flowthrough said opening and chamber to fill the container when said valvestem is in a first position, and further wherein said valve operates toseal the container to prevent filling and discharge of the containerwhen said valve stem is placed in a second position forcing said valvecore beyond said protrusion and into contact with said valve seat.
 8. Anon-refillable valve, as claimed in claim 7, wherein: said valve corefurther includes a sealing member attached thereto which contacts saidvalve seat in the second position.
 9. A non-refillable valve, as claimedin claim 7, wherein: said valve stem has a bore formed therein, and saidvalve core is slidably received in said bore and movable in said bore asinfluenced by the positioning of said valve stem and by pressure of afluid entering or exiting said valve.
 10. A non-refillable valve, asclaimed in claim 7, wherein: said valve stem is positionable in a thirdposition to allow flow of fluid out of said pressure container and backthrough said chamber and said transverse opening; however, said thirdposition preventing flow of fluid through said transverse opening andsaid chamber into the pressure container, thus preventing the refillingof the container.
 11. A non-refillable valve, as claimed in claim 10,wherein: said third position is defined by said valve stem being raisedto a level allowing said valve core to slide upward in response to fluidpressure from the container, or slide downward in response to pressurefrom fluid entering the chamber, said downward movement of said valvecore causing said valve core to seal itself with respect to said valveseat.
 12. A non-refillable valve adapted for use with a pressurecontainer, said valve comprising: a valve body having an inner surfacedefining a chamber extending therethrough, said chamber communicatingwith the pressure container to allow selective filling and discharge ofthe container, said inner surface having means extending into saidchamber for creating a constriction in said chamber, said chamberfurther including a lower portion communicating with a transversepassageway formed in said valve body, said transverse passagewayintersecting said means for creating a constriction; means mounted insaid chamber for controlling flow of fluid through said valve, saidmeans for controlling including a flange; means for positioning saidmeans for controlling, said means for positioning mounted in saidchamber and placed in contact with said means for controlling; andwherein said means for positioning enables said means for controlling tomove from a first position to a second position, said first positionenabling fluid flow through said valve to fill the pressure container,said second position preventing fluid flow to and from the pressurecontainer; and means for sealing positioned between said inner surfaceof said valve body and said means for positioning.
 13. A non-refillablevalve, as claimed in claim 12, wherein: said means for controlling isslidably received in said means for positioning.
 14. A non-refillablevalve, as claimed in claim 12, wherein: said means for positioningincludes a valve stem mounted within said chamber, and a handle attachedto said valve stem.
 15. A non-refillable valve, as claimed in claim 12,wherein said means for positioning enables said means for controlling tobe positioned in a third position to allow flow of fluid from thepressure container and back through said valve, yet prevents fluid flowthrough said valve and into the pressure container, said means forcontrolling being independently movable with respect to said means forpositioning while said means for controlling is in said third position.16. A non-refillable valve, as claimed in claim 12, wherein said meansfor sealing comprises at least one o-ring.
 17. A method of controllingflow to and from a pressure container, said method comprising the stepsof: attaching a valve to the pressure container, the valve communicatingwith an opening of the pressure container, the valve including a valvebody defining a chamber therein, a valve stem inserted within the valvebody, the valve stem including a slidable valve core inserted within abore of the valve stem, a protrusion extending from an inner sidewall ofthe valve body into the chamber, the protrusion intersecting atransverse passageway that opens into the chamber, and a valve seatlocated at a lower end of the valve in the chamber; setting the valve toa first position wherein the valve core is positioned in the chamberabove the protrusion; providing a first flow of fluid through the valveand into the container for filling the container with a desired fluid;operating the valve to move the valve core downwardly beyond theprotrusion and in seating engagement with the valve seat of the valve,thus sealing the pressure container; operating the valve to a third openposition allowing fluid to evacuate from the container back through thevalve.
 18. The method as claimed in claim 17, wherein the valve coreincludes a flange having a substantially flat upper edge and a sealingmember attached to a distal end of the valve core.
 19. The method asclaimed in claim 17, wherein said distal end of the valve coreintersects or is positioned above the transverse passageway duringfilling.
 20. The method as claimed in claim 17, further comprising thestep of providing a second flow of fluid into the valve, thereby causingsaid valve core to slide downwardly with respect to the valve stemcausing the valve core to return to its seated position against thevalve seat, thereby preventing flow of the second fluid into thepressure container.
 21. A method of controlling flow to and from apressure container, said method comprising the steps of: attaching avalve to the pressure container, the valve communicating with an openingof the pressure container, the valve including a valve body defining achamber therein, a valve stem inserted within the valve body, the valvestem including a slidable valve core inserted within a bore of the valvestem, the valve core including a flange having a substantially flatupper edge and a sealing member attached to a distal end of the valvecore, a protrusion extending from an inner sidewall of the valve bodyinto the chamber, the protrusion intersecting a transverse passagewaythat opens into the chamber, and a valve seat located at a lower end ofthe valve in the chamber; setting the valve to a first position whereinthe valve core is positioned in the chamber above the protrusion;providing a first flow of fluid through the valve and into the containerfor filling the container with a desired fluid; operating the valve tomove the valve core downwardly beyond the protrusion and in seatingengagement with the valve seat of the valve, thus sealing the pressurecontainer; operating the valve to a third open position allowing fluidto evacuate from the container back through the valve.
 22. Anon-refillable valve adapted for use with a pressure container, saidvalve comprising: a valve body having an inner surface defining alongitudinally extending chamber extending therethrough, said chamberhaving a lower portion communicating with the pressure container toallow selective filling and discharge of said container, said chamberincluding a valve seat positioned in said lower portion of said chamber,said inner surface having a concentrically oriented protrusion extendingfrom said inner surface into said chamber, and a transverse openingformed in said valve body adjacent the protrusion and communicating withsaid valve chamber; a valve stem disposed in said chamber and beingmovable in said chamber, said valve stem including a valve corecommunicating with said valve stem, said valve core being independentlymovable in said chamber relative to said valve stem, said valve coreincluding a flange; and a first O-ring and a second O-ring abutting saidinner surface of said valve body for sealing said valve stem withrespect to said valve body; wherein said valve operates to allow fluidto flow through said opening and chamber to fill the container when saidvalve stem is in a first position, wherein the valve core is in anuncompressed state within said chamber when said valve stem is in saidfirst position, and further wherein said valve operates to seal thecontainer to prevent filling and discharge of the container when saidvalve stem is placed in a second position, the second position achievedby extending an end of said valve stem below said protrusion and forcingsaid valve core beyond said protrusion and into contact with said valveseat.
 23. A non-refillable valve adapted for use with a pressurecontainer, said valve comprising: a valve body having an inner surfacedefining a longitudinally extending chamber extending therethrough, saidchamber having a lower portion communicating with the pressure containerto allow selective filling and discharge of said container, said chamberincluding a valve seat positioned in said lower portion of said chamber,said inner surface having a concentrically oriented protrusion extendingfrom said inner surface into said chamber, and a transverse openingformed in said valve body and communicating with said valve chamber,said protrusion intersecting said transverse opening; a valve stemdisposed in said chamber and being movable in said chamber, said valvestem including a valve core communicating with said valve stem, saidvalve core being independently movable in said chamber relative to saidvalve stem, said valve core including a flange; and at least one O-ringabutting said inner surface of said valve body for sealing said valvestem with respect to said valve body; wherein said valve operates toallow fluid to flow through said opening and chamber to fill thecontainer when said valve stem is in a first position, and furtherwherein said valve operates to seal the container to prevent filling anddischarge of the container when said valve stem is placed in a secondposition, the second position achieved by extending an end of said valvestem below said protrusion and forcing said valve core beyond saidprotrusion and into contact with said valve seat.